Computing attachment for type-writers.



W. WRIGHT.

COMPUTING ATTACHMENT FOR TYPE WRITERS.

APPLICATION FILED APR. 1907. RENEWED JULY T, 1909.

1 1 60,102. lutvnwd Nov. 9, 1915.

m n ISHEETS" SHEET 1. a s5;

W. WRIGHT. COMPUTING ATTACHMENT FOR TYPE WRITERS. APPLICATION r1120 APR. 1. 1901. RENEWED JULY 1, 1909.

Patented Nov. 9, 1915.

7 SHEETS-SHEET 2.

W. WRIGHT. COMPUTING ATTACHMENT FOR TYPE WRITERS; APPLICATION FILED APR. 1'. 1901. RENEWED JULY 1, 1909.

Patented Nov. 9, 1915.

e. m m .H ,M H .1 WAQNMWN m W ZZZLCD'I LIIIII m3 NR nHnes w. WRIGHT. COMPUTING ATTACHMENT FOR TYPE WRITERS. APPLICATION FILED APR. 1. I907.

RENEWED JULY 1, I909.

Patented Nov. 9, 1915.

7 SHEETSSHEET 4.

W. WRIGHT.

COMPUTING ATTACHMENT FOR TYPE WRITERS. APPLICATION FILED APR. I, 1907. RENEWED JULY I, I909 1,1 0,102, Patented Nov. 9, 1915.

7 SHEETSSHEET 5.

Jim/6107 7313 ZMW ffowoe v- W. WRIGHT.

COMPUTING ATTACHMENT FOR TYPE WRITERS. APPLICATION FILED APR. 1, 1907. RENEWED sun/1.1909.

1,1 60,1 02. Patented Nov. 9, 1915.

7 SHEETS-SHEET 6.

HELIX II II III I T; gun- I!" UNITED STATES PATENT OFFICE.

WALTER WRIGHT, OF SAN FRANCISCO, CALIFORNIA, ASSIGNOR', BY MESNE ASSIGN- MENTS, TO UNDERWOOD COMPUTING- MACHINE COMPANY, A CORPORATION OF NEW YORK.

COMPUTING ATTACHMENT FOR TYPE-WRITERS.

Specification of Letters Patent.

Patented NOV. 9, 1915.

Application filed April 1, 1907, Serial No. 365,886. Renewed July 1, 1909. Serial No. 505,492.

To all whom it may concern:

Be it known that I, VALTER WRIGHT, a citizen of the United States, residing at San Francisco, in the county of San Francisco and State of California, have invented new and useful Improvements in Computing Attachments for Type-Vriters, of which the following is a specification.

The object of the present invention is to provide a computing attachment for typewriting machines, which can be attached with comparative ease to any of the standard forms of such machines, which will be simple and inexpensive in construction, which will add at the same time a considerable number of separate and independent columns of figures corresponding with numerals written in similar columns by the typewriter, or, when desired, will perform the operation of subtraction in any column or at any part of said column.

In the accompanying drawings, Figure 1 is a front view of a typewriting machine equipped with my improvement; Fig. 1 is a vertical transverse section through one of the key levers; Fig. 2 is a detail side view of one of the shutters; Fig. 3 is a side view showing one of the arms by which the computing carriage is moved with the typewriter carriage; Fig. at is an enlarged front view, partly broken away, of the operating mechanism at one end of the machine; Fig. 5 is a longitudinal sectional view of the transmitter carrier and the controller, taken on the line 55 of Fig. 6; Fig. 6 is a side view of the controller; Fig. 6 is a view of the other side of the controller;'Fig. 7 is an enlarged view of one of the pins in the controller; Figs. 8 and 9 are side views of the escapement wheel in difierent positions; Figs. 10 and 11 are front views of the same in the corresponding positions; Fig. 12 is a broken enlarged front view of computing and figure wheels and the mechanism immediately cooperating therewith; Fig. 13 is a transverse section of the same looking from the left; Fig. 14 is a similar view looking from the right; Fig. 15 is a front view of the locking lever and the releasing lever; Fig. 16 is a horizontal section on the line 1616 of Fig. 1%; Fig. 17 is a detail front view showing one of the computing wheels and a primary transfer wheel adapted to be engaged thereby, detached; Fig. 18 is a sectional view of the computing wheels; Fig.

18: is a perspective View of a transfer wheel; F 1g. 19 is a broken longitudinal view of the shaft carrying the figure wheels; Fig. 20 is a cross sectional View of the same; Fig. 21 1s a side view of one of the figure wheels; Fig. 22 is a plan View of said shaft; Fig. 23 is a side view of the internal parts of said shaft showing the teeth withdrawn; Fig. 24

is a broken side view of the computing shaft, the tubes'being shown in section; Fig. 25 is a cross-section of said shaft; Fig. 26 is a broken plan view of the same; Fig. 27 is an enlarged side view of the error-correcting knob; Fig. 28 is a sectional view of the same; Fig. 29 is an end View of the computing attachment; Fig. 30 is a front view of part of the driving mechanism therefor; Fig. 31 is a view of an end plate of the attachment, viewed from the inside; Fig. 32 is an end view of the attachment to the computing carriage, for effecting a transfer from one wheel to the next; Fig. 33 is a broken front view of the same; Fig. 3% is a detail side view of the partitions in the computing carriage; Fig. 35 is a front view of the same; Fig. 36 is a broken detail view of the device for eflecting the subtraction; Fig. 37 is a detail sectional view of a part of the controller. Fig. 38 is a diagrammatic side elevation of the wellknown Monarch typewriting machine with my improvements connected thereto.

Uomwczfion.-Referring to the drawings, 1 (Fig. 1) indicates the frame of a typewriting machine, which may be of any standard construction, but, for the purpose of illustration, is herein shown as a Mom arch machine. Secured upon the right hand side of the frame is a plate 2 having an extension or arm 3. at the end of which is supported a vertical plate l. Secured upon the extension 3 is a ring 5 through which pass wires or rods 7 attached at their left hand end to bell crank levers 8, to the other arms of which levers 8 are attached links 9, which pass through apertures 10 in a shift bar 11. Each link 9 is formed at its lower end into a hook 12, which by the movement of the shift bar 11, is adapted to be moved into an aperture 13 in a collar 15 secured upon the lever ll of one of the numeral keys 16 of the machine. By sliding the bar 11 to the left. all of said links can be caused to engage their respective apertures 18, and, by this means, the computing mechanism can be made ready for operation. 4 To move said shift'bar- 11 to the left, there is pro- 'vided a three-armed lever '17 attached to said shift bar and also to two key stems 18 and 19. By depressing the stem 18, the

counting attachment is operatively con nected with the numeral keys, and by depressing the stem 19, it is disconnected there? from.

,=-pivotally mounted on the ring 5'. By the movement to the left of one arm ofa bell crank lever-20, theother arm of'said lever is moved against the end of a, .jack or slidable transmitter rod'22, said rods sliding in apertures 23 in acylindrical transmitter carrier 24 supported on the extension 3, the left end of said rods being bent outward at 29 and iadaptedto slide in'slotted guide rods 27, around whichguide rods are coiled compression springs 28 tending to press said I rods 22 to the left and toward the center of carrier 24, the latter movement being limited by pins 26' which close the ends of the slots in the. 1 061927. Thereby, by the movement of any numeral key,- the corresponding transmitter rod 22 is pushed to the right.

Since the rods 22 slide in grooves upon the.

face of the transmitter carrier, and since their bearings 1n the carrler'are sufiiciently shortand loose, they can swing outward when impinged upon by the levers 20 in their outward movement, and thus permit the levers -20.to return.

Upon a shaft 25, having a bearing in the plate 4, is secured a primary escapement wheel or rotary controller 30-, which is formed with a circular series of ten holes or slideways 31' '(Fig. 6), in which are loose 'escapement teeth or bolts 32 of greater length .than the holes,. their ends on the left being adapted to abut against the inner sides of the radial arms 33 of small detents in the form of bell crank levers 34 pivoted in slots formed in a wall 30 in said controller, the detent arms 36 of said bell crank levers being pressed downward by a circular helical or coiled spring ring 37 around all of said arms 36. By this means the radial arms 33 of said bell crank levels are all extended leftwardly or away from said controller. When any oneof the numeral keys is actu- Med, and thereby the corresponding transmitter rod 22 is pushed to the right, said rod strikes the radial arm. '33 of the bell crank lever 34 which has been brought opposite thereto,,and moves said arm to the right, the end of the controller being recessed below said wall 30* to allow said arms bolt 32 to the right so that it projects out of the controller. The bell crank lever 20 con rod 22, whereupon, said rod immediately returns by the action of the spring 28, freeing the bell crank lever 34, so-that the controller is .free to-rotate. The bell crank lever 2. can freely return on the release of the nuv meral key, since the end of the rod 22 is moved radially outward by the end of said bell crankleveras it passes; The controller is formed with a circumferential groove intersecting the apertures 31, so that the ends of the arms 36 bear down-on the bolts 32; said bolts being formed with recessed portions or necks 68 to receive said arms. The movement of each bolt is limited in one directionbv the plate 4, and in the return direction by'the arm 33 of the bell crank .lever 34, the radial arm 33 of which is prewhich a computing shaftg35 is rotated. I

will now describe the mechanism for rotating said shaft. Said shaft 35 extends-between the plate' 4, and a frame 38 secured on the left hand side of the frame of the type,- writing machine; On the end of said shaft extending through the plate 4 is a bevel gear 39, which is engaged by a bevel gear 40 on a-shaft 41 carrying a bevel gear 42 meshing with a bevel gear 43.0n the shaft 25, said shaft being driven by a gear wheel 44 thereon meshing with a gear wheel 45 on a stud shaft also carrying a bevel gear 46 meshing with a bevel gear 47 on a power shaft 49, which is under torsional strain from the constantly applied force of driving mechanisni hereinafter described. On account of t-hex connection of the shaft 25 with the power, the controller 30 tends to rotate whenever permitted to do so by certain feeding or releasing mechanism. This releasing mechanism is operated by the depression of a numeral key as follows :Suspended bv links 50 from the frame of the 'typewriting gaged by a corresponding bell crank lever- 8, so that, on the operationpf a numeral key, the corresponding pin 52 being engaged by its bell crank lever, the universal bar is moved to the left, The end of said univer-- sal bar on the right is connected to a crank arm 53 on the shaft 54' mounted in bearings 55 on the plate 4; and on said shaftis carried an escapement device,- which comprises two dogs or disks 56, 57 having cut out from their edges recesses or openings 58, 59 (Figs. 10, 11) offset from each other, for the purpose of permitting and controlling the passage through them of one of a series of lugs'or teeth 60, on a secondary eseapement Wheel 61, (Figs' 8, 9) four of such lugs being here shown. Said wheel 61 is on a shaft 62, which extends through the plate 4 and carries a star wheel or pinion 63 having the same number of points or teeth as there are lugs 60 on the escapement wheel 61, these pointsbeing adapted, by the rotation of said pinion, to be brought into the path of one of the teeth or bolts'32 extruded from the controller by the .operation of a numeral key. Previous to the depression of any numeral key, another bolt 32 which has been so extruded bythe next preceding depression of a numeral key still remains extending out from the controller and in engagement with a point of the star wheel 63. .the star wheel being held from rotating by the pressure (hereinafter explained) of a lug of the secondary escapement wheel 61 against the first of the escapement dogs 6 as in Figs. 8 and 10. Upon the depression of a numeral key, the crank 53 is moved to the left, which causes the escapement or dog device to rotate through a small angle into a position to permit the lug 60 on the secondary escapementwheel to pass through the opening 58 in the edge of the first disk. This it immediately does, as shown in Figs. 9 and 11, being actuated so to do by the pressure against the pinion of the bolt 32 which was last operated. (Fig. 6) and this pressure, again, is produced by the force constantly applied to the power shaft :9 and transmitted to the controller shaft 25. Consequently. as regards thecomputing. the depression of the key accomplishes two results, first, it extrudes from the controller 30 a bolt 32 "corresponding to the particular numeral key depressed. and, second, it moves the secondary escapementwheel a slight distance, into a position so that the tooth thereof which was in engagement with the first disk 56 is now between the two disks 56 and 57 of the escapement device; and these parts remain in this position until the key is re leased by raising the finger. As soonas the operators'finger is raised to release the key, a spring 64 moves the universal bar 51 to the right, thereby moving the crank 53 to the right, and the upper portion of the es capement device to the right, and thereby moving the opening 59 in the second disk 57 of the escapement device into such position that the tooth 60 upon the secondary escapement wheel 61 can pass through it.

The-secondary escapement wheel being now,

perfectly free to rotate, the star wheel 63 no longer resists the pressure from the previously operated boltv 3'2, but permits the primary escapement wheel or controller to rotate, the secondary escapement wheel 61 also rotating through nearly a quarter of a revolution, until the next tooth 60 thereon brings 'up against, the first disk 56 of the escapement device, which is now in such a position that; the tooth cannot pass through ceding operation.

responding to a given extent of rotation of the controller, the computing shaft 35 is also rotated, and, as hereinafter described, it imparts rotation to the computing mechanism. As the controller 30 rotates, the bolt which previously engaged the pinion 63, and has been permitted to pass the same, engages the face of a wedge 66 extending inwardly from the plate 4, and is, by the said wedge,'returned to its normal position in the controller ready for subsequent use. The two disks 56 and 57 are,' by means of set screws 56, 57, secured upon the shaft 54: adjustably, to permit the escapement to be used with any particular action of the typewriter, so that the controller can be released either on the downward stroke of the key, or on the return thereof.

Computing mechanism.-The computing shaft 35 rotates but has no longitudinal movement. Secured to said computing shaft are one or more teeth 70, (Figs. 14, 24:, 25, 26) two being here shown. Surrounding the shaft 35 are two tubes 71, one on each side of the central teeth 70, which are provided primarily for the purpose of reducing the friction of said shaft and permitting it to turn more easily, and on said tubes are supported a series of computing wheels 72, corresponding to letter spaces of the typewriting machine. These computing wheels move with the typewriter carriage 82 to the' left and thus pass in succession over the teeth 70 extending from the computing shaft; and of said computing wheels only that one immediately over or around said part of the shaft carrying said teeth is directly operated by the rotary movement of said shaft. Each computing wheel is formed as an internal gear wheel having ten recesses or notches 73, and, as the typewriter carriage moves to the left, a pair of opposite notches, on each wheel 72 in succession, are brought into engagement with the two teeth 70 on the computing shaft, no matter in what angular position said teeth were left by the last pre- Consequently, when the computing shaft 35 is rotated, by the mechanism heretofore described,.upon the depression or release of any numeral key, the computing wheel which is in engagement with the teeth 70 of said shaft is correspondingly rotated. Said computing wheel is formed with external gear teeth 74, which mesh with a pinion 75, which in turn mesh with gear teeth 76 formed at the side of a figure wheel 77, the face of said wheel carrying the figures 0 to 9. Consequently, said figure wheel is given a rotation corresponding in extent to that of the computing shaft 35, and to the particular numeral-key depressed.

A casing 78 is provided, (Fig. 12') covering the figures of all the .figure wheels 77 except one row, the figures of which indicate the result of the computation made. For instance, if any figure wheel stands so that the figure 7 is displayed, and'then the numeral key 2 is depressed,then, upon the depression or release ofsaid key, said figure wheel isadvanced so that the figure 9 is displayed. The carriage'79 which carries the computing wheels 72 is separated into compartments-by vertical partitions 80 consisting of thin plates which pass between adjacent computing and figure wheels, and they brace and stre'ngthenthe computing carriage'7 9. The carriage is provided with gear wheels 108 (Fig. 1) which run on a rack 81, and is advanced with the typewriter carriage 82 by means of arms 83 extending forward from the typewriter carriage and carrying fingers 84 pivoted on the ends of said arms, which, when moved down, engage the ends of the computing carriage 79, and

move itwith the typewriter carriage. When said fingers are moved up and thrown back, as shown in dotted lines at Fig. 3,,the computing carriage 79 can be' longitudinally moved independently of the typewriter carriage.

TransfeMng.-In order to carry on from one/wheel to the next when a number is added to the previous number on said wheel so as to make the total greatervthan nine,

there is formed at one side o f'each computing wheel 72 a-lug'or tooth 85, (Figs. l3, 17, 18,) which, in the rotation of the computing wheel, is brought into engagement 'with a tooth 86 on a primary transfer wheel 88 loose on a shaft 88, said tooth 85 belng such wheels stand at .9,. or in the position in which the transfer is to be effected to the wheel of the next higher denomination, and it is necessary that all of said transfers should bemade at once, which they'would necessarily do if made directly and without such auxiliary mechanism, the resistance caused by having to transfer so many wheels nism. Such a condition, although occurring very rarely, is possible, and such tardiness of operation might vitiate the accuracy of the machine. As a' means of avoiding this objection, I provide an auxiliary mechanism the main element of which is a'secondary transfer shaft 90. For convenience, the mechanism for operating this shaft will be described later. For the present it is suflicient to say that said transfer shaft rotates in the direction shown by the arrows in Figs. 13 and 14 when the operation is that of addition, and in the opposite direction when the operation isthat of subtraction. The transfer is therefore'eifected in the following manner: When the lug 85, moving in the direction of the arrow shown in Fig. 13, has made a complete revolution 'with the computing wheel 72 upon which it is formed, it impinges against'the rear side rapidly, for the reason hereinafter described, the leading rib .of the next following pair of ribs 90 will impinge against the rear side of the wide tooth 86, and will complete the advance of the primary transfer wheel. As said primary transfer wheel 88 is thus advanced, the wide tooth 86 immediately following the narrow tooth 86 which was so actuated by the lug 85, passes between the somewhat wide teeth 89 of the next computing wheel 72 to the left, and, by engagement with said teeth, advances said computing wheel through one-tenth of a revolution, then assuming the position shown in Figs. 13 and 14:, in which the next narrow tooth 86 is then in positionto be engaged by the lug 85 after another complete revolution of the corresponding computing wheel.

The reason why the ribs on the secondary transfer cylinders 90 are made in pairs, is to provide for the operation of subtraction as well as addition, the leading rib 90 in either direction of motion of said cylinder being the operating rib.

I will now describe in detail the manner in which the secondary transfer shaft 90 is rotated. "However, the invention is not limited to the specific means here shown for accomplishing this purpose. Saidtransfer shaft extends (Fig. 1) between the two end plates of the carriage 79, parallel with the computing shaft. This shaft 90 is rotated with the movement of the computing carriage '79, and for this purpose, said shaft has secured on each end bevel gears 96,*Fig. 33, and these gears 90 mesh with bevel gears 97 on transverse shafts 98, carried by the ends of the computing carriage, and carrying on their rear ends pinions 99, Fig. 32, which mesh with gear wheels 100, Figs. 1, 32 and 33, which are loose on transverse shafts 101, also carried by the computing carriage. On the front ends of said shafts 101 are secured the gear wheels 108 which mesh with the stationary rack 81. As the computing carriage travels to the left, the gear wheels 108, being thereby rotated in the direction of the arrow in Fig. 33, rotate the shafts 101. Secured to said shafts 101, in front of the gear wheels 100, are notched wheels 104, and on the faces of the wheels 100 are pivoted the double pawls 105 having central arms 106, the ends of which are pressed, to one side or the other, by fiat springs 107, secured at 210 to the faces of the wheels 100. Each spring 107, therefore, tends to maintain one of the noses 105 of its corresponding pawl in engagement with a notch of the corresponding wheel 104. But by reason of said nose 105 being to one side of the pivot of the pawl 105, said pawl operatively engages said notched wheel 101 when the latter isrotating in onedirection only. The two pawls 105 are oppositely arranged, so that when either operatively engages its notched wheel, the other may be adjusted to slip over its notched wheel without en-' right handed rotation to the secondary transfer shaft 90, looking along said shaft to the left; but the pawl 105 at the left end of the carriage will be adjusted.toinoperative position. lVhen the carriage returns,

' the pawl 105 on the right will be inoperative, and that on the left operative, and it will be readily seen that the connection is such as to rotate the secondary transfer shaft 90 in the same direction as before. By placing the pawls in the Fig. 1 position,

the carriage 79 may be locked against travel in letter spacing direction. By now shifting either one pawl or the other from the Fig. 1 .position.,the mechanism will be set for either addition or subtraction as the case may be. It may be here stated that the object of using two-nosed pawls is to employ the secondary transfer shaft 90 for subtracting, when desired, as will be more fully hereinafter explained. lVhen it is desired to sense it, the relative positions of the pawls 105 are changed from Fig. 1, so that the other nose of one pawl is now pressed the spring against the notched wheel 104.

Upon thereafter shifting both pawls the efand 100 should be proportioned to give the shaft 90 a third of a revolution at each let ter-feeding movement of the carriage, which in typewriting practice varies from to Q; of an inch. The shaft 90 is shown diagrammatically. In'its normal position, a line drawn through the axes of 88 and 90 should pass midway between the teeth in a pair on the remote side of 90 from 88. So the couplingtooth 86 normally should occupy a position in direct line with the axes of 35 and 88, so as to'have an equal movement in either direction under the thrust of starting tooth or lug 85;

It has already been stated that the computing wheels are arranged to correspond with the typewriting spaces of the typewriter. They are, however, arranged in groups of three, corresponding to three such typewriter spaces, each group being spaced from the next adjacent group an interval corresponding with the fourth such typewriter space. The intervening space between the figures of the figure wheels 77 may be occupied by a period or comma or may be left blank, but such intervening space in either case serves to divide such figures into groups of three. In other words, the whole line of figures displayed by the machine will be divided into groups of three, each group being spaced from the next adjacent. group by an interval not more than one typewriter space, and the three computing wheels of a group corresponding to three such typewriter spaces. This arrangement enables the operator to insert commas or periods at the end of each group of three figures just in the same way as in ordinary typewriting, so that the hundreds are shown plainly divided from the thousands, and the hundreds of thousands from the millions, and so on. At the same time the construction is such as to permit of carrying from the computing wheel on the left of any groupto the computing wheel on the right of the nextadjacent group to the left, through the intervening space between the two groups. For this purpose, every third computing wheel 72 and the corresponding figure wheel 77, are each made of an excessive width, as compared with the other two. computing or figure wheels, so as to extend across said intervening spaces between the groups of figure wheels, and the primary transfer wheels 88 corresponding to the transfer wheels 88 are also made correspondingly wide. An extra wide computing wheel 72 is shown in detail in Fig. 18, having a wide instead of each wide tooth of the latter, the former has two separate teeth 86 86*, in

axial alinement with each other, the differ ence being one of form only. In the case of the narrow wheel 88, these two teeth join each other and form one wide tooth 86, whereas, in the case'of the wide wheel, the'teeth are separated from each other a distance corresponding to a typewriter space. The extra wide computing wheels 7 2 differ from the other two .computing wheels 72 only in havinganextra deep crown flange 72, which is made of suflicient depth to occupy the space between adjacent groups, It may be here observed that when the teeth 70 upon the computing shaft 35 arrive at the space immediately within this deep crown flange 7 2, they are inoperative to turn any computing wheel. It therefore follows that, as the typewriter carriage'and computing carriage move successively through type- I writer spaces, the teeth 70 of the computing shaft 35 are successively brought intothree operative positions, in which they can engage computing wheels, and then, at the fourth such movement, into a position in which-they are inoperative, havingarrived at the space within the crown flange 72' of a wide computing wheel. Fromthisit results that should the operator strike a numeral key in the wrong position, that is, out of one of the columns of figures, this would cause no change in the figures, for, although the computing'shaft 35 would be rotated thereby, the teeth 70 of said shaft would be revolving in a position in which they could notengage any computing wheel.

Each partition 80 may be formed with a curved rib109, Figs. 12, 34 and 35, which at the part appearing through the cover strip in the casing 78, may be formed with a period or a comma to correspond with the point ofseparation into groups of three wheels. The result is that the entire row of characters appearing through the cover strip is divided into groups of three numerals, the groups being separated by one typewriter letter space. It will have been perceived that in the present invention aconsiderable number of separate columns may be added at the same time. But, when any part of a group of computing devices is not being used, the corresponding wheels will show-the numeral 0 through the cover strip, and therefore, in order to'avoid uncertainty as to the termination of the figures making the-total, there are provided small shutters 110,.Figs. 1 and 3, which can slideon a rod 111 to cover 'otally mounted upon a bar 113 extending and independent should not by any possibility move from their proper position except when positively advanced'by mechanism for that purpose. To insure this I provide the following locking mechanism: For each computing wheel there is provided a lockin lever 112, (Figs. 13, 14, and 15) all of sai levers being pivlongitudinally between the ends of the computing carriage. Each lever has a recess or notch 114 which is adapted to engage any one of the teeth 89 formed upon the corresponding computing wheel 72. Said lever 112 is normally pressed against the primary transfer wheel by means of a spring 115, and the end of the same arm is formed with a beveled head 116 which, when the primary transfer wheel 88 begins to rotate, is moved outward by the tooth 86 of said wheel, and so moves the locking lever from its locking position. Said transfer wheel is locked against accidental rotation by means of a spring 117 having a hump 118 which passes between any one of the pairs of teeth on said transfer wheel.

At the.depression of a numeral key, the arm 206 rises, Fig. 4, permitting spring 131, Fig. 29, to lift rod 129 and rock up arm 128'idly. Upon the return of the key, arm

206 forces down the rod 129, pulling down 7 arm 128, striking the trip 126 on arm 125, and swinglng down thelatter until the tip of arm 128 passes by the trip 126. However,

arm 125 is held down by means of latch 136 (see Fig. 31), which holds up arm 134 (connected through 133, 132 and 122 to said arm 125), said arm 134 having been elevated above said trip 136 by the action ofarm ping past the trip 126, which is snapped into position again by the spring 127.

Releasing mechanism.It is, of course, necessary to release said locking lever 112, in order to rotate the computing wheel 72, and for this purpose there is provided a finger 119, (Fig. 15) which is pivoted in a fork 120 on a collar 121 secured upon a longitudinal rock shaft 122 which extends between the plate 4 and frame 38 and has bearings therein. -Said collar 121 is secured in such position on said shaft 122 that it lies in the same vertical plane as the teeth 70 on the computing shaft 35. Consequently, it acts only upon the locking lever corresponding to the computing wheel which,

, having arrived at that point of the shaft 35, which carries the teeth 70, is in position to be rotated by the turning of said shaft. The end of the finger 119 lies immediately behind a releasing arm 123, extending outwardly and rearwardly from said lever 112, and, upon the rocking forward of said finger 119, said arm 123 is also rocked forward, moving the notch 11 1 in the lever 112 out of engagement with a tooth 89 on the computing wheel 72 and releasing said wheel. To so rock said finger 119 forward there is secured upon the end of the rock shaft 122, adjacent the right side of the plate 4, an arm 125, (Fig. 29) upon which is pivoted a stop 126, which is normally depressed by a spring 127. Opposite said' stop 126 is arranged apivoted arm 128 from which depends a hanger rod 129 having a pin 130 adapted to be engaged by a crank 206 on the shaft 54. 'On the depression of a numeral key, said crank 206 is raised and releases the hanger rod 129, which rises under the action of a spring 131, the arm 128 at the upper end of said rod likewise rising and escaping past the end of the pivoted stop 126, which then drops back into place under the action of, the spring 127. Then upon release or depression of the numeral key, the hanger rod 129 againdescends, so that the arm 128 depresses the stop 126, and rocks the shaft 122, moving the finger 119 forward, withdrawing the locking lever 112.

To maintain said locking lever in its position of release, thereis secured on the rock shaft 122, adjacent the left side of the plate 4, a rearwardly extending arm 132, from which depends a hanger rod 133, attached at its lower end to a pivoted arm 134:, pulled down by a spring 135. A latch 136 is pivoted at 137 on the plate 4, andwhen the arm 13% is raised by the rocking of the shaft 122 to actuate the releasing means to withdraw the locking lever 112, the upper end of the latch 136 is adapted to be pressed bv a spring 138 beneath the end of said arm 134, holding it up, and maintaining the locking mechanism inoperative (Figs. '29 and 31).- The locking lever 112 is held in the position in which the computing wheel is unlocked, until the controller 30, carrying the bolts 32, has almost completed its movement due to the release of the numeral key, and the bolt 32 which has just been extruded from the controller has almost arrived at the star wheel stop'63,* the end of its course. Just before it so arrives,-'saidbolt strikes the lower end of the latching lever 136 and forces it outward, thereby swinging its upper end away from the end ofthe arm 134,

and permitting the rock shaft 122 toreturn to its original position, which it immediately does. This only takes place when the controller 30 has arrived at the position of rest, Figs. 6 and 29, and immediately the notch 114 in the locking lever 112 engages the tooth 89 opposite thereto of the computing wheel 72, and insures that the figures of the figure wheels 77 will be in exact alinement. The construction of the computing mechanism permits the use of the ordinary typewriter escapement in which the advance of the typewriter takes place on the release of the numeral key (although, if desired, the reverse escapement could be used for the typewriter carriage). The computing mechanism is operated after the typewriter key has been depressed and while said key is returning to original position. The typewriter carriage is let off at the last part of the return stroke of the typewriter key. As the key rises, the computing wheel 72 which at the moment is at the printing point is turned by the master wheel 70,- this occurring before the carriage starts, or at least before-72 is out of mesh with 70. The finger 119, which releases the locking lever 112, is

pivote'd, so as to'permit of a lateral swing when engaged with the locking lever, the amplitude of this swing being the same as a typewriter letter space. By so pivoting this finger 119 the releasing arm 123 is permitted to engage said finger 119, notwithstanding the movement of the carriage (Fig. 15). The locking levers of the computing wheels which may have been already acted upon by the releasing finger 119, are released only at the instant that the transfer is made from the wheel 72 corresponding to the next lower denomination, and this is efl'ected by the same movement of the primary transfer wheel 88 which advances the computing wheel 72 one-tenth of a revolution, this being accomplished-by a wide tooth 86 of the transfer wheel 88 engaging the head 116 of the lever 112 of the corresponding computing wheel and pushing said lever .112

away from said computing wheel 72.

Resetting mechanism-In order to reset all the figure wheels 77 to zero, the following mechanism is provided: Said wheels turn loosely upon a tube 1&0 (Figs. 19, 23,) hav ing a longitudinal series of apertures 1+l1,

through which extend teeth 142 formed upon a fiat bar 143. Said bar slides between two approximately half-round rods 14% connected by pins 145, which pass through oblique slots 116 in the flat bar 143. The rods 14% are connected at one end with a knob 147. By pushing said knob'to the left, said pins, acting in said slots, push the fiat bar 1-13 outward, so that the teeth 142 project beyond the apertured tube, as in Figs. 19 and 20. Each tooth is then in position to engage a radial lug 148 of the figure wheel 77 extending into a cavity formed therein. But before said wheels can be reset-to zero they must be unlocked. This is effected by means of an eccentric shaft 149 carrying a small knob 150 on its end projecting through the right-hand side of the casing 78, (Figs. 13, 14 and 20), said eccentric bearing against anupwardly extending arm 151 of each locking lever 112. Upon turning said knob, the movement of the shaft 149 causes the wide "part of the eccentric to engage said arms 151, and thereby move the locking levers 112 out of engagement with the computing wheels 72, permitting said computing wheels and'ngure wheels 77 to turn freely. Then,'to reset to zero, the knob 147 is first pushed to the left, and then rotated, whereupon the teeth 142 are first projected and then rotated, until they strike the lugs 148, which happens sooner or later with the several wheels 77 according to the position in which they have been left by the previous computation, and since these lugs 148 extend from all the figure wheels 77, the effect will be to bring all of said Wheels into register with each other as regards the figures. Said wheels can thus be turned back so that all the zeros thereon appear at the slot in the casing 78. The'knob 147 is then moved to the right, which withdraws the teeth 142 into the slotted tube, leaving the wheels free to rotate, and the Knob 150 is turned= back to its normal position.

:Error correction.1t is desirable to provide means forcorrecting an error made by inadvertently striking the wrong numeral key of the typewriting machine. Should the operator,.in order to correct an error made by depressing the wrong key, move the car riage back two, spaces, to bring the printed numeral one letter-space to the right of its original position, the same movement will bring the computing wheelowhich has just been operated one space to the right of, and out of engagement with the teeth of the computin shaft. On the left hand end of the tube 1 which'su'rrounds the right-half of the computing shaft 35 isformed a correcting tooth 153, (Figs. 24,26) the normal position of which will be in line with one of the recesses 73 of the internal gear teeth of the computing wheels 72, so that,. by the said movement of two spaces to the right,-

said tooth is caused to engage such a recess. Thereby said computing wheelI can be turned back to any desired position, preferably the original position before the wrong numeral, key was struck. Suppose, for instance, the operator] intended to strike ,the numeral key 6, but by inadvertence struck the numeral key 7, then it would be 'de sirable to turn back the computing wheel 72 seven-tenths of a revolution, and then move the computing carriage 7 9 one space made. For this purpose the knob 150 (Fig.

29) is turned until the wide part of the eccentric on shaft 149 (Fig. 14) swings the arm 151 of the locking lever 112 forwardly and thereby moves said locking lever'out of engagement with the computing wheel 72, permitting said computing wheel and associated figure wheel 77 to turn with the tooth 153 on the sleeve 71. Fast on the right-hand end of said sleeve is a pinion 154 (Figs. 26 and 31) which meshes with a pinion 156 fast on a shaft 157. Loosely mounted on' the shaft 157 is a knob 158 the left-hand end of which has ten notches 159 formed therein, adapted to engage pins 160 fast on the shaft 157, and has the O. to 9 marked on its periphery, one of the numerals opposite each notch. After the computing wheel 72 has been unlocked to correct an error, the knob 158 is turned until the same number thereon as had been erroneously written is brought opposite the bent upper end of a depressor rod 167. The knob 158 is then moved leftward along theshaft 157 until the notches 159 engage the pins 160. When the knob 158 is turned back to zero, the same angular motion is transmitted to the figure wheel 77, thus restoring said wheel to its previous position. The knob 158 carries a pin 166 (Figs. 26, 29) which, as the knob is turned back to zero, engages the bent upper end of the depressor rod 167 connected to a lever 169 engaging an arm 171 extending from the latch 136, which was engaged by a pin extruded from the controller upon the operation of a numeral key, which latch 136 is now, however, engaged by said lever 169 original position by-setting the computing mechanism to addition, and then moving the carriages 82 and 79 back one letter-space, and depressing the same numeral key as had been erroneously depressed. 1

An error is corrected by the use of the correction mechanism, in the following manner: Assuming that the operator by mistake has written and added 7 instead of 2. The carriage is now in such position that the tooth or master-wheel 70 engages the wheel of next lower denomination to that on which the error was made. The paper carriage is therefore retracted one step, to bring the erroneously driven wheel into register with the master-wheel 70 and the lock-releaser 119, Figs. 11, 15. The knob 158 is then rotated until 7" thereon shows at the index (Fig. 29). and then the knob is thrust to the left from the position at Fig. 26 to the position at Fig. 28, with the spurs 160 (on shaft 157) engaging the internal gear 159 with which said knob 158 is provided (Fig. 27). By reason of such endwise thrust of the knob 158. the arm 162 (Fig. 4) is canuned down. rocking shaft 163 (Fig. 29) depressing arm 16% on said shaft. This arm engages pin 165, Fig. l, and thrusts down link 129, rocking down the arm 128 (Fig. 29). which, by engagement with the. trip arm 126 pivoted on arm 125. rocks down said arm 125, rotating the shaft 122, and swinging the arm 119 thereon forwardly into engagement with the releasing arm 123 of the locking dog 112 belonging to the computing wheel at the moment in engagement with the master wheel. This releases said computing wheel, so that it can he rotated. Next, the carriage is set back an additional letter-space, to bring the released computing wheel into-engagement with the correcting pin 153, Fig. 26. last movement of the carriage, the releasing arm 119 swivels upon its vertical pivot on the collar 121. to accommodate the lateral movement of the arm 123 and locking dog 112: said releasing arm 119 being notched (Fig. 15) to have a locking engagement with said arm 123 for this purpose. (Said releasing arm 119 may swivel to either right or left, one of such movements being illustrated in dotted lines at Fig. 15). The erroneous computation wheel being now released from its dog and also in engagement with the correction pin 153, Fig. 26, the knob 158 is rotated seven points, until the figure 0 thereon shows at the index; this rotation being in subtraction direction or counterclockwise at Fig. 29. Or, looking at Fig. 31. it will be seen that the rotation of the knob-shaft 157 is in clockwise direction at this time. This movement is-communicated through pinion 155 to gear 154, which also moves in clockwise direction at Fig. 31, viz.. in direction for subtraction; said gear 154 being fixed to hollow shaft 71, carrying the correction-pin 153, which moves the engaged computation Wheel 72 backwardly seven points. The knob 158 may then be returned along shaft 157 to normal Fig. 26 nosition. this movement being accompanied by a release of cam arm 162, whereby the During this.

dog-releasing arm 119 is permitted to be returned to normal position by spring 135, Fig. 29, so'that the computation wheel just rotated may be re-locked by its dog 112. The numeral type key 2 may now be struck. the erroneous number 7 on the work-sheet having first been erased. Thus the error may be corrected while the machine still remains ,in condition for addition. hether the number erroneously written is larger or smallerv than the correct number, the process of correction may be the same, first to'rotate the computation wheel backwardly to cancel the number computed, and then to insert the correct number in the wheel by the operation described. In this manner correction may proceed along as many wheels as necessary, by correcting the wheels one at a time. It is also apparent that the position of a number wheel may be altered by rotating the same by the knob 158, whether a new number is thereupon inserted in said wheel or not. Vhenever the machine is set for subtraction, the direction of rotation of the correcting knob 158 must be the reverse of that just described, in correcting an error. For instance, if 4 has been subtracted instead of 3, the knob 158 must be turned in a direction to add 4 in the number wheel; and thereupon the key for 3- may be struck, to subtract that amount. Thus provision is made for correcting such errors, whether the machine is set for addition or subtraction. If the correction involves several number wheels, when adding, the operator may resort to the expedient of setting the machine for subtraction, to subtractout the numbers on the "arious wheels, and may then restore the machine to condition for addition, and proceed to add the correct numbers. A contrary course may be pursued if the machine is subtracting when an error is made involving several wheels.

Driving meclzanism.-The motive power is here shown as derived from a spring which may be wound up either automatically by a reciprocating motion of the typewriter carriage or voluntarily, bya crank, at suitable intervals. I will describe only the modification in which the spring is wound up automatically, it being then unnecessary to describe themechanism for winding by hand.

The usual spring 175 (Fig. 30) for advancing the typewriter carriage is now placed at the right of the machine, and a band 176 (Figs. 1, 29) connected to the casing 177 of said spring is passed around an idle wheel 178 (Fig. 1) and thence to the typewriter carriage. Said casing 17 7 carries a pawl 179 which engages a tooth of a wheel 180 loose on a fixed shaft 181, and thereby, when the carriage is retracted to begin a new line on the machine, said casing is rotated and imparts rotation to the wheel Said wheel 180 has formed thereon a gear wheel 182 which ngages a pinion 183 loose on a shaft 184, an connected by a sleeve 185 With a casing 186 secured to the outer end of the spring 187, the inner end of said spring being attached to the shaft 184. Said casing 186 has formed thereon a gear wheel 188 which meshes with a pinion 189 connected by a ratchet clutch 190 with the shaft 19 to permit the carriage 82 to be run back and forth even though no computing is done. The spring 187 thus continually furnishes power to rotate the shaft 49 and is itself wound up by means of the casing or drum 177. In this way force is constantly applied to drive the computing shaft.

Subtracting The attachment may also be used' for subtracting. For this purpose the bevel gear'40 is moved away fromthe bevel gear 39, and a bevel gear 201, (Fig. 36)

pposite toithe gear 40, is secured on the shaft 41 so "as to mesh with the gear 39. The shaft 35 will now be driven in the reverse directiomwhich will effect the .operation of subtracting. Instead of the means shown for shifting and securing these gears, any

common shifter can be used, an example of which is seen in the patent to KaussemNo. 747,977, in which the shifter 211 may be shifted along the drive-shaft 41, to connect either pinion or pinion'201 thereto; the

shifter being operated by the usual handle 212,

I claim 1. In a computing device, the combination,

I with key levers, of a transmitter carrier,

meral-key, to protrude one end of the corresponding bolt beyond said controller,and resetting meansfadapted to engage said protruded end of the bolt, and return the bolt to its normal position, said bolt being of such magnitude relative to the controller, that its other'end protrudes from the slide-way of said bolt insuch normal posit on, substantially as described.

2. In a computing device, the combination,

with key levers, of a transmitter carrier,-

movable devices supported by sa-id carrier, a rotary controller, bolts slidable therein, and adapted to be brought opposite to said devices, computing mechanism, means for con! trolling said computing mechanism the rotary movement of the'controller, said demechanism, a rotary controller therefor,

bolts carried by said controller and movable relatively thereto, a stop for said bolts, and means for selectively protruding a bolt into a position to be arrested by said stop upon the rotary movement of the controller, said means, when protruding the bolt, being 10- cated outside of said controller, substantially as described.

4. In an apparatus of the character de- 1 scribed, the combination, of computing mechanism, a rotary controller therefor,

bolts carried by said controller and movable relatively thereto, a stop for said bolts, 7

devices for selectively protruding a bolt into a position to be arrested by said stop upon the rotary movement of the controller, means for selectively operating said devices upon the downward movement of a numeral key, and means for returning said devices to their normal position during said down ward movement, substantially as described.

5. In an apparatus of the character described, the combination of numeral keys, computing mechanism, a rotary controller therefor, bolts slidablein said controller, spring-resisted devices adapted to engage said bolts to protrude them from the controller, and levers, operated upon the depression of a numeral key, and engaging said devices during part only of the forward movements of said levers, to cause said devices to abut against said bolts, said levers being free toreturn past said devices on the return movement of the levers, substantially .as described.

6. In a computing attachment for'type writers, the combination of key levers, wires adapted to be operatively connected with the key levers, bell crank levers connected with the otherends of the respective wires,

a transmitter carrier, rods slidably sup-.

ported therein, adapted to be moved in said carrier by the other arms of said levers, springs for returning said rods to their norbell crank levers pivoted "on said controller,-

said levers being adapted to be moved by the 'transmitt'er'rods and also adapted to move thecontrollerbolts. a spring around; a

the outer arms of all the levers, computing mechanism,- and means for controlling said computing mechanism by the rotary movement of the controller, substantially as described.

7. In a computing attachment for typewriters, the combination of key levers, wires adapted to be operatively connected with the key levers, bell crank levers connected with the other ends of the respective wires, a transmitter carrier, rods slidably supported therein, adapted to be moved in said carrier by the other arms of said levers, springs for returning said rods to their normal position, the ends of said rods being movable laterally to permit the bell crank levers to return, a rotary controller, bolts slidable therein and adapted to "be brought opposite to the rods in the transmitter carrier. bell crank levers pivoted on said controller, said levers being adapted to move the controller bolts, a spring; around the outer arms of all the levers, computing mechanism, and means for controlling said computing mechanism by the rotary movement of the controller, substantially as described.

8. In a computing attachment for typewriters, the combination of key levers, wires adapted to be operatively connected with the key levers, bell crank levers connected with the other ends of the respective wires, a transmitter carrier, rods slidably supported therein, adapted to be moved in said carrier by the other arms of said levers, springs for returning said rods to their normal position, said rods being movable laterally to permit the bell crank levers to return, a'rotary controller, bolts slidable therein and adapted to be brought opposite to the rods in the transmitter carrier, bell crank levers pivoted on said controller, said levers being adapted to be moved by the transmitter rods and also adapted to move the controller bolts, a spring around the outer arms of all the levers, said controller being formed with a circumferential groove and the bolts being formed with recesses to receive the arms of the bell crank levers passing through said grooves, computing mechanism, and means for controlling said computing mechanism by the rotary movement of the controller, substantially as described.

9. In an apparatus of the character described, the combination of numeral keys, computing mechanism, a rotary controller therefor, operating mechanism therefor, an arresting device for arresting said controller, means for providing rotational pressure to withdraw said arresting device, an escapement mechanism for preventing its withdrawal, and means whereby said escapement mechanism may be actuated with the operation of a numeral key to release the means for withdrawing said arresting device, substantially as described. 7

10. In an apparatus of the character described, the combination of computing mechanism, a controller therefor, a rotary stop for arresting said controller, means for rotating said stop, escapement mechanism for preventing its rotation, and means actuated with the operation of a numeral key for actuating said escapement mechanism to first release and then arrest said stop, substantially as described.

11. In an apparatus of the character described, the combination of numeral keys, computing mechanism, a controller therefor, a rotary stop for arresting said controller, means for rotating said stop, and an escapement comprising a device rotating with said stop, a rock shaft adapted to be rocked with the operation of a numeral key, and parts carried by said rock shaft offset from each other, and adapted to successively engage said device in different angular positions of the rock shaft to arrest the device, substantially as described.

12; In an apparatus of the character described, the combination of numeral keys, computing mechanism, a controller therefor, a stop for arresting said controller, means for providing pressure to withdraw said stop, an escapement operatively connected with said stop, and a device arranged to be operated by a numeral key and having parts respectively adapted in different positions of said device to successively arrest said escapement, substantially as described.

13. In an apparatus of the character described, the combination of numeral keys, computing mechanism, a controller therefor, means for arresting said controller, an es-- capement for releasing said arresting means, and an operative connection between said escapement and a numeral key, whereby, in the downward movement of a numeral key, the escapement is permitted to move a part only of its complete releasing movement, and to complete said releasing movement upon the return movement of the numeral key, substantially as described.

14. In an apparatus of the character described, the combination of numeral keys, computing mechanism, a rotarv controller therefor, means independent of the operation of the numeral keys for rotating said, controller, a rotary device adapted to first release and then arrest the controller, and

means controlled by the operation of a numeral key for first releasing and then arresting said device, substantially as describe 15'. In a computing attach'ment for typewriters, the combination of numeral keys, a computing shaft, driving mechanism therefor, and means for releasing saidshaft to permit it to be rotated by the driving mechrf; anism, comprising a universal bar, means whereby said bar is shifted by'the operation.

of any one of the numeral keys of the type- Writer, a. shaft operatively connected with troller when the previouslyextruded bolt is released,controlled by the movement of the typewriter key for releasing the latter bolt, a wedge engaging theend ofthe last named bolt to return it to its normal position, andcomputing mechanism variably controlled by the rotation of said controller, substantially as described.

17. In a typewriting and computing ma- .chine, having devices arranged to print at a common point,-the combination of numeral k eys, a paper carriage, a computing carriage, means whereby the computing carriage is moved with the 'paper carriage'and in the same direction one typewrit'ing space at a time by the operation of a numeral key,

[computing devices movable with said computing carriage, a shaft passing through said computing devices, a suitable support foi 'said'ishaft, and meanfs 'for imparting a variable rotation to saidshaft dependently upon the operation-of a numeral key, said shaft being provided with means, located substantially opposite to the common printing point of the machine, for successively engaging said computing devices to impart rotary motion thereto, substantially as described. f. v g

'18. In atypewritingand computing machine,the combination of, numeral keys, a

paper carriage, a computing carriage, means whereby the computing carriage is moved with the paper carriage and in the same direction one typewriting space at a time by the operation. of a' numeral key, computing devices movable withsaid computing carlia'ge, a shaft pa'ssing through said comput- 7 I said computing jing devices, a suitable support for'said shaft, I

andrmea'ns foriimpai'ting a variable rotation to said shaft dependently upon the operation ofa numeral key, said shaft beingv provided withmeans for successively engaging devices to impart rotary mo tion thereto, substantially as described.

19,111 a typewriting and computing ma chine, the combination? of "numeralkeys, a-

paper carriage, a computing carriage, means -whereby the computing carr age is moved $5 with the paper carriage and in the "same direction one typewriting-space ata time by the operation of a key, computing devices movable with said computing carriage,

a shaft passing through said computing devices, a suitable support for said shaft, means for imparting a variable rotation to said shaftdependent upon the operation of a numeral key, said shaft being provided with means for successively engaging said computing devices to impart rotation thereto, and tubes within the computing devices and surrounding said shaft except at. said means, and secured independently of the shaft, substantially as, described.

20. In a typewriting and computing machine, the combination of numeral keys, a paper carriage, a computing carriage, means whereby the computing carriage is moved with the paper-carriage and .in the same direction one typewriting space at a time by the operation of a key, computing devices movable with said computing carriage, a

shaft passing through said computing devices, a suitable support for'said shaft, means for imparting a variable rotation to said shaft dependently upon the operation of a numeral-key, said shaft being provided with means for successively engaging said computing devices to impart rotation thereto, and a fixed tubular means around said shaft and within the computing devices to separate said computing devices therefrom, substantially as described.

21. In a computing device, the combination-of a series of computing wheels, numeral keys to operate them seriatm, means actuated by the arrival of each computing wheel at a predetermined point in its rotation for advancing the next computing wheel one-tenth of a revolution, and an assisting mechanism to-operate saidmeans for, effecting said advance, said assisting mechanism effective at the numeral key operation.

I 22. In a computing device, the combination of a series of computing wheels, nu-

meral keys to operate them seriatz'm, a series of transfer wheels adapted to carry from one wheel to' the next of a higher denomination, and an assisting mechanism effective at the numeral key operation and rotated independently of the rotary movement of the computi'ngmechanism, and arranged to engage a transfe wheel when the latterhas been brought to a predetermined point by the rotary movement of a computing wheel, and assist the turning of, said transfer wheel.

23. In a computing device, the combination of 'a series of computing wheels, 3, series of transfer wheels to carry fromone wheel "to the next of a higher denomination, and an. assistingmechanism actuated by the, movement of a denomination-contrQlling computing carriage and rotated independently of the rotary movement of the com v putmg mechanism, and arranged to engage aitransrer wheel when the latter has been brought to a predetermined point by the rotary movement of a computing wheel, and assist the turning of said transfer wheel.

24. In a computing device, the combination of a series of computing wheels, numeral keys to operate them serialim, a series of transfer wheels to carry from one wheel to the next of a higher denomination, and an assisting shaft having teeth thereon adapted when the transfer wheel has been brought to a predetermined position to engage the teeth of said transfer wheel and assist them in turning, said assisting shaft effective at the operation of-any numeral key.

25. In a computing device, the combination of a series of computing wheels, transfer wheels adapted to carry from one wheel to the next of a higher denomination, an assisting shaft having teeth thereon adapted when the transfer wheel has been brought to a pre-determined position to engage the-teeth of said transfer wheel and assist them in turning, and means actuated by the movement of the computing carriage in either direction for rotating said assisting shaft in the same direction and rotated independently of the rotary movement of the computing mechanism, substantially as described.

26. In a computing device, the combination of a series of computing Wheels, a series of transferring wheels for carrying from one computing wheel to the next of a higher denomination, an assisting shaft having a part adapted to engage said transfer .wheels when moved into apre-determined position to assist their rotation, a longitudinal rack, a gear wheel, rotatablv attached to the carriage and meshing with said rack, and an operative connection between said gear wheel and the shaft, whereby the shaft is rotated by the rotation of the gear wheel when the carriage is moving in one direction but is disengaged there from when the carriage is moving in the opposite direction. substantially as described.

27. In a computing device, the combina-' tion of a series of computing wheels, a series of transferring wheels for carrying from one computing wheel to the next of a higher denomination, an assisting shaft having a part adapted to engage said transfer wheels when moved into a pre-determined position to assist their rotation, a longitudinal rack, a gear wheel at each end of the carriage meshing with said rack, and a connection be tween each gear wheel and the corresponding end of the assisting shaft, alternately operative when the carriage is moving'in one direction and inoperative whenv it is moving in the opposite direction, substantially as described.

wheels and transfer wheels, and means 0p erated'at the movement of the carriage for actuating said shaft.

29. In an apparatus of the character described, the combination of a series of computing wheels, a tube therethrough having a longitudinal series of apertures, and a device in said tube movable longitudinally therein, said device and bar having, the one an oblique slot and the other a pin engaging said slot, to project said teeth upon the longitudinal movement of said device, substantially as described.

30. In an apparatus of the character described, the combination of an apertured tube, a series of wheels thereon, a bar in said tube having a part adapted to project through said aperture, means for preventing the longitudinal movement of the bar, a device in said tube adapted to move longitudinally therein, said device and bar having, the one an oblique slot and the other a pin engaging said slot, whereby, on the longitudinal movement of said device, said part is projected'from said tube, substantially as described.

' 31. In an apparatus of the character described, the combination of a tube having a series of apertures, wheels thereon, one over each aperture, a bar in said tube having oblique slots, and teeth, one adapted to project through each aperture, a rod on each side of said bar, pins connecting said rods through rparts rigid therewith and adapted to engage the respective wheels when so moved transversely, a device movable longitudinally of said support, and connections between the two devices whereby from the longitudinal movement of the one is produced a transverse movement to the other, substantially as described.

33. In apparatus of the character described, the combination of a series of apertured computing wheels, a shaft passing through said wheels, a tube surrounding said shaft and having a laterally projecting tooth thereon, and means for turning said tube to turn any desired computing wheel.

34;. In an apparatus of the character de- 

